Refrigerating system



Feb. 12 1924.

L. PENWELL REFRIGERATING SYSTEM Filed Feb. 5. 1921 3 Sheets-Sheet 1 a Sheets-Sheet 2 Filed Feb. 5. 1921 L PENWELL REFRIGERATING SYSTEM 3 NW ww Feb. 12 1924.

Feb. 12 1924.

L. PENWELL REFR LGERATING SYSTEM 3 Sheets-Sheet 5 Filed Feb. 5

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Patented Feb. 12, 1924.

": S T AT ES PATENT OFFICE. A

LENIS PENWELL, OF CHICAGO, ILLINOIS, ASSIGNOR, BY

' REFRIGERATOR CAR EQUIPMENT COMPANY, A CORPORATION OF WASHINGTON.-

REFRIGERATING SYSTEM.

Application filed February 3, 1921. Serial No. 442,071.

tems, of which the following is a specification.

This invention is related to refrigeratning systems of that type wherein the refrigerant is circulated by the movement of the vehicle while in transit, a concrete example of which is disclosed in Letters Patent of the United States No. 1,219,570 to McCoy, 1h dated March 20, 1917.

The present invention has to do with the adaptation of a system of the general type mentioned to trucks for the transportation and delivery of frozen products, such as ice cream, ices and the like, and its primary object is toprovide a system of this character in which the circulation of the refrigerant by the movement of the vehicle is supplemented by utilizing certain physical laws, thereby providing for higher efliciency and reduced cost in obtaining the desired refrigeration, as well as procuring circulation while the vehicle is at rest.

A further objectof the invention'is the provision of a refrigerating system which is adapted to the general purposes indicated and wherein the parts are so related and combined that a relatively large volumeof the refrigerant may be employed without diminishing storage or refrigerating space of the vehicle, but, on the contrary, enabling this space to be increased. This permits the use of a larger vehicle body. and-attains the transportation and delivery of greater load. 1

The invention seeks to provide for the accomplishment of other objects and advantages which will become apparent as the nature of the improvements is better .understood, the invention consisting substantially in the novel construction, combination and arrangement of parts-hereinafter fully described, illustrated in the accompanying drawings, and finally pointed out in the appended claims.

'While one form of the invention has been disclosed, it is to be understood that the same is not to be restricted thereto, the present disclosure being a preferred embodiment andto be considered, therefore, from the illustrative standpoint andnot as im posing restrictions on the invention.

In the drawings- Fig. 1 is a vertical longitudinalsectional view, taken on a medial line, of the'body of a delivery truckequipped with the hereindescribed invention;

Fig. 2 is a vertical transverse sectional view thereof on the line 2'2, of Fig. 1 and Fig. 3 is a sectional plan VlGW on the Referring now in detail to the accompanying drawings, the numeral 10 desig-' nates the body of" a delivery truck or similar vehicle designed for the transportation of frozen products, such as ice cream, ices and similar commodities. The walls of this body'lO are insulated, as at 11, by suitable material designed for this purpose, and the low temperature imparted to the interior of the body 10 is thus free from the external temperature conditions. The] body 10 is provided with a door 12 at one side thereof, or av plurality of doors. ma be employed, to affl'ord access to the interior. The latter, except'as hereinbefore indicated,

may be utilized in its entirety for storage missus ASSIGNMENTS; To

of the goods to be transported, and this in-'* terior, therefore, constitutes a refrigerating chamber. v

Extending transversely of the interior :of the body 10, and arranged adjacent to one of its ends, is a vertical bulkhead 13', and between said bulkhead and the adjacent end of the body is located a pair of reare frigerant tanks 14: and 15. These tanks' separated by a vertical partition 16, and adjacent to the lower end of said partition the latter is formed with a plurality of ports 17 by which communication is afiorded between said tanks. These ports are controlled by valves 18 of any suitable construction, but valves of the flap type preferably are employed, The valves are arranged at the side of the partition 16 in order to lie within the tank 14, and while permitting passage of the refrigerant from the tank 15 intothe tank 14; the valves 18 preclude return of the refrigerant through the ports 17. The tank 14 constitutes the source of supply of the refrigerant to the ICU circulatory units hereinafter referred to,

lie

It will be observed that the tanks 14 and 15 extend from the bottom to the top of the body 10, and the roof of the latter has formed therein hatch openings 19 and 20 which are arranged over the tanks 14 and 15 and covered by suitable closures 21 and 22. Through the hatch openings 19 and 20 ice and salt may be introduced to the tanks 14 and 15, and upon meltage of the ice the refrigerating brine is formed.

Located at the interior of the body 10, and supported from the top thereof by suitable hangers 23, is a plurality of circulatory units each of which is formed of a U-shaped pipe 24. One leg of each of these pipes 24 is provided with a vertical feed extension 25 which projects downwardly and is connected to a horizontal pipe section 26 which enters the supply tank 14 at its lower end. The other leg of each of the pipes 24 is also provided with a vertical discharge extension 27 which projects downwardly and is located within the receiving tank 15. At this point it'is to be observed that the feed extensions 25 are at the interior of the body 10, thus exposed to the relatively high temperature of such interior, while the discharge extensions 27 are disposed within the receiving tank 15 and are subjected to the relatively low temperature of this tank. This arrangement of said extensions 25 and 27 has a dis tinct function and will be adverted to later herein.

The horizontal pipe section 26 connected to each of the feed extensions 25 terminates in a vertically disposed nozzle 28 within the supply tank 14, and included in each of said nozzles 28 is a valve 29 the stem of which extends through the adjacent end of the body 10 at which point it is provided with an operating handle 30. These valves operate independently of each other, and the nozzles 28 are connected transversely by nipples 31 which constitute a header. Connected to the header thus formed is a vertically disposed primingpipe 32 which rises through the tank 14, its upper end extending above the roof of the body 10. The pipe 32 is closed by a cap 33. a

The discharge extensions 27 are likewise provided within the receiving tank 15 with vertically disposed nozzles 34, and said nozzles 28 and 34 have associated therewith screen caps35 for preventing the sediment and dbris entering the pipes with which the several nozzles are connected.

For the purpose of draining the tanks 14 and .15 the lower ends thereof haveconnected thereto valved outlets 36, and when the valves of said outlets are opened the brine within said tanks may be withdrawn therefrom.

In "the operation of the hereindescribed refrigerating system the several pipes 24 are primed with water introduced through the priming pipe 32 and fed thereby into the header 31. To effect this priming the valves 29 are operated so as to shut off communication through the nozzles 28 between the interior of the tank 14 and the pipes 24. The water will, therefore, rise in the feed extensions 25 and pass into the pipes 24 until the required level of water has been reached to maintain the pipes in their primed condition. Upon introduction of ice and salt into the tanks 14 and 15 brine will be formed as the ice melts. The valves 29 having been further operated to shut off communication with the priming pipe 32, but to establish communication between the pipes 24 and the interior of the tank 14 the brine may now enter the nozzles 28 for passage to the pipes 24. It has been mentioned at a previous point herein that the primary circulation of the brine is effected by movement of the vehicle in transit. The swaying of the body 10 in this movement causes the valves 18 to open when the body is tilted in one direction in respect to its transverse diameter, and the liquid in the receiving tank 15 thereupon will flow into the supply tank 14, thereby establishing a greater head of pressure in the tank 14 than in the tank 15. When the body 10 has righted the valves 18 close against their seats, thus preventing the refrigerant passing back into the tank 15, and by reason of the increased head of the refrigerant in the tank 14 that portion of the refrigerant which is in the pipes 24 is given further movement in its travel therethrough. As the refrigerant passes through the pipes 24 it follows a uni-directional path, because of the valves 18 controlling the ports 17, and these valves. act to insure such movement of the refrigerant throughout the operation of the system. So long as the level of the refrigerant in the tank 15'is lower than the level thereof in the tank 14 the pipes 24 act in the capacity of siphoning elements, and this siphoning action supplements the swaying movement of the body 10 in promoting circulation of the refrigerant through the pipes 24.

As before stated, the feed extensions 25 are subject to the relatively high temperature of the refrigerating chamber of the body 10, while the discharge extensions 27 are subject to the relatively low temperature of the receiving tank 15. By reason of this arrangement of said extensions 25 and 27 that portion of the brine passing into the feed extensions 25 will be slightly raised in temperature, and its specific gravity thereby becomes relatively lighter, but as the brine passes into the discharge extensions 27 its temperature becomes relatively lower, and its specific gravity becomes relatively heavier. This latter condition, therefore, as the column of brine passes through each discharge extension 27, causes a pull on the brine within the pipes 24, andvas the rela-- tively lighter portions of the brine within the feed extensions 25 have a tendency to rise, it is obvious that circulation of the brine will be promoted because of this difference in the relative specific gravities of the portions of the brine in the extensions 25 and 27. The circulation of the brine thus will be effected when the vehicle comes to rest and is no longer subject to the swaying movement imparted thereto while in transit.

From the foregoing description it will be seen that the hereindescribed refrigerating system adds to the advantages of thecirculation established by'the swaying movement of the vehicle the further advantages of circulation induced by invoking natural physical laws, and the system affords higher efficiency with economy in consumption of ice, as well as attaining a greater volume of the refrigerant due to the fact that the tanks l l and 15 may extend from the bottom to the top of the body 10, thereby increasing the capacity of these tanks over those hitherto employed in systems of this general type.

The nozzles 28 and 34 with their respec tive pipe connections with the extensions 25 and 27 constitute traps for the several pipes 24: to preserve the primed condition of these pipes. Should, therefore, the level of the brine become lower than'the upper extremities of said nozzles the pipes 24 remain primed. This excludes air from the pipes 24: and materially prevents corrosion of said pipes.

While the invention has been described as incorporated in delivery trucks for frozen products, it will be understood that the same is not to be restricted to such use, it being obvious that its utility extends to all vehicles designed for the transportation of perishable products of any character.

I claim:

1. In a system of the class described, the combination with a body having a refrigerating chamber therein, of a plurality of circulating units arranged in said chamber, a pair of refrigerant tanks arranged exteriorly of said refrigerating chamber, one of said tanks serving as a source of supply and the other serving to receive the refrigerant discharged by said units, said tanks communicating with each other for effecting transfer of the refrigerant from the receiving tank to the supply tank, means for preventing back-flow of the refrigerant in its circulation, whereby to insure uni-directional movement of the refrigerant through the tanks and units, feed extensions connected to said circulatory units and communicating with the interior of the supply tank, said feed extensions being subject to the relatively high temperature of the refrigerating chamber, and discharge extensions also connected to said circulatory units,

said dischargeextensions being located within the receivingtank and subject to the relatively low temperature thereof, whereby to vary thespecific gravity ofthe refrigerant at separated points to maintain circulation of the same'through the units.

2. In a system ofxthe class described, the combination with a body having a refrigerating chamber therein, of a plurality of refrigerant in its circulation, whereby to in sure uni-directional movement of the refrigerant'through the tanks and units, depending feed extensions connected to said circulatory pipes and having communication with the interior of said supply tank, said feed extensions being located within the refrigerating chamber and subject to the relatively high temperature thereof, and discharge ex tensions also connected to said circulatory pipes, said discharge extensions being located in said receiving tank and subject to the relatively low temperature of the latter, whereby to vary the specific gravity of the refrigerant at separated points to maintain circulation thereof through said pipes.

3. In a system of the class described, the

combination with a body having a refrigerating chamber, of a plurality of circulatory pipes arranged in said chamber adjacent to its top, said pipes being U-shaped and nested, a pair of refrigerant tanks arranged exteriorly of said refrigerating chamber, one of said tanks serving as a source of supply and the other serving to receive the refrigerant discharged by said units, said tanks communicating with each other for effecting transfer of the refrigerant from the receiving tank to the supply tank, means for preventing back-fiow of the refrigerant in its circulation, whereby to insure uni-directional movement of the refrigerant through the tanks and pipes, depending vertical feed extensions connected to said circulatory pipes and communicating with the interior of said supply tank, said feed extensions being arranged in the refrigerating chamber and subject to the relatively high temperature thereof, and depending vertical discharge extensions also connected to said circulatory pipes, said discharge extensions being located in said receiving tank and subject to the relatively low temperature of the latter,

whereby to vary the specific gravity of the refrigerant at separated points to maintain circulation thereof through the pipes.

.i j acent to its top, a pair of refrigerant tanks arranged exteriorly of said refrigerating chamber, one of said tanks serving as a source of supply and the other serving to receive the refrigerant discharged by said pipes, said tanks communicating with each other for effecting transfer of the refrigerant from the receiving tank to the supply tank, means for preventing back-flow of the refrigerant in its circulation, whereby to insure uni-directional movement of the refrigerant through the tanks and pipes, depend ing vertical feed extensions connected to said circulatory pipes and communicating with the interior of said supply tank, nozzles arranged within said supply tank and connected to said feed extensions, means for priming the circulatory pipes, valves associated with said nozzles and controlling communication between said circulatory pipes and said priming means, said feed extensions being arranged within said refrigerating chamber and subject to the relatively high temperature thereof, and depending vertical discharge extensions also connected to said circulatory pipes, said discharge extensions being located within said receiving tank and subject to the relatively low temperature of the latter, whereby to vary the specific gravity of the refrigerant at sepa- 5. In a system of the class described, the

combination with a body having a refrigerating chamber, of a plurality of circulatory pipes arranged in said chamber adjacent to its top, a refrigerant supply tank arranged at one end of said chamber, feed extensions connected to said pipes and extending downwardly therefrom, said feed extensions being connected to and communicating with said supply tank, a receiving tank for the refrigerant discharged from said pipes, discharge extensions extending downwardly from said pipes, "the feed extensions being located within the refrigerating chamber, and the discharge extensions within the receiving tank, whereby the refrigerant within said extensions is subject to the relatively high temperature of the refrigerating chamber and the relatively low temperature of the receiving tank to vary the specific gravity of the refrigerant at separated points to maintain the circulation of the same through said pipes.

In testimony whereof I have hereunto subscribed my name in the presence of two subscribing witnesses.

LEWIS PENWELL.

Witnesses:

JUSTINE Or'rorr, C; SHORTREED. 

